Vehicle transport

ABSTRACT

A vehicle transport including a low-bed trailer in which the spaced side frames of the superstructure, except for the connection between their bottom edges, are interconnected solely by vertically adjustable horizontal cross-ties on which the forward ends of track assemblies are swingably supported for vertical adjustment, the rear ends of the respective track assemblies being vertically adjustable independently of their forward ends. All of the supporting and adjusting means for such assemblies are located within vertical planes common to the respective side frames of the trailer.

United States Patent Taylor [54] VEHICLE TRANSPORT [72] Inventor: GlennEdward Taylor, P.O. Box 93006 Martech Station, Atlanta, Ga. 30318 [22]Filed: Dec. 11, 1970 [21] Appl. No.: 97,187

[52] US. Cl. ..296/l A, 105/368 R [51] Int. Cl. ..B60p 3/08 [58] Fieldof Search ..296/1 A; 105/368 R [56] References Cited UNITED STATESPATENTS 3,145,043 8/1964 Gyori et a1. ..296/1 A 3,084,970 4/1963 Day..296/l A 2,461,927 2/1949 Schaldach ..296/1 A 3,104,127 9/1963Swartzwelder ..296ll A 1 Sept. 12, 1972 Primary Examiner-Benjamin HershAssistant Examiner-John A. Pekar Attorney-Watson, Cole, Grindle & Watson[5 7] ABSTRACT planes common to the respective side frames of thetrailer.

6 Claims, 12 Drawing Figures I Patented Sept. 12, 1972 5 Sheets-Sheet lXTTOF/VEYS Patented Sept. 12, 1972 5 Sheets-Sheet 5 z/ m n M PatentedSept. 12, 1972 3,690,717

5 Sheets-Sheet 4.

//v vE/v 70/2, 64 5W5 74%05 Patented Sept. 12, 1972 5 Sheets-Sheet 5VEHICLE TRANSPORT This invention relates to improvements in a vehicletransport of the type including a tractor trailer combination in whichthe trailer has a super structure defined by relatively spaced verticalside frames between which are disposed and supported various frames ortracks, including vertically movable upper tracks on which vehicles aresupported, other vehicles being disposed within the trailer between theside frame thereof.

In vehicle transports of the type above described, it has been customaryfor the relatively spaced sideframes or panels of the trailer, to beinterconnected adjacent their upper edges by suitable fixedcross-members or ties for contributing to lateral stability of theentire superstructure. Even where the track assemblies for supportingthe uppermost tier of vehicles have been swingably supported from thesecross-ties, the crossties or cross frame members have neverthelessconstituted immovable obstacles restricting the height of vehiclesloaded into the carrier therebeneath. Moreover, even though one end onlyof the track assembly or frame, may be supported by such a fixedcross-member or cross-tie, the said end is accordingly deprived of anyvertical adjustability, making it impossible to adjust the height ofboth ends to fully utilize the space available therebeneath forefficient placement of vehicles. Even in instances where such trackassemblies have been vertically adjustable, no provisions have been madefor independently vertically adjusting the opposite ends of each suchframe or track assembly and the vehicle supported thereby so as fully toutilize the space available in the carrier while securing the lowestpossible center of gravity and the lowest possible overhead clearancefor passage beneath overpasses and the like. Because of theselimitations, many prior vehicle carriers have been limited to thehauling of certain specific makes and types of the vehicles in certainspecific arrangements, particularly adapted to the measurements andshapes of the respective vehicles.

In accordance with the present invention, the sole interconnections orcross-connections between the proposed sideframes or panels of thetrailer superstructure above the trailerbed are vertically adjustablethroughout very substantial ranges of adjustment whereby to be capableof movement out of the path of the vehicles during movement and storageof the latter within the trailer. Such connections at the same time, byfirmly interconnecting the side frames or panels of the superstructure,contribute to their lateral stability to resist both swaying andrelative lateral movement between the side frames.

Moreover, in accordance with the invention, such connections in the formof guide bars or cross-ties between the side frames are utilized aspivotal supports for one end of an upper track assembly, power meansbeing provided for vertically adjusting such tie-bars. Means are alsoprovided for supporting and vertically adjusting the opposite end ofeach such track assembly, the opposite ends of the assembly thus beingindependently vertically adjustable, whereby the assembly and anyvehicle supported thereon may have its opposite ends separately andindependently adjusted to a minimum height or level as permitted byvehicles therebeneath, thus to achieve a low center of gravity for theloaded carrier and to achieve a minimum clearance or overhead tofacilitate passage beneath bridges and overpasses.

In accordance with certain specific features of the invention, there isincluded a novel disposition of a middle track assembly and means forindependently adjusting the height of the opposite ends thereof wherebya vehicle may be supported thereon between the upper and lower tiers ofvehicles in a minimum amount of space at whatever angle and dispositionof its opposite ends may be necessary in order to secure clearance withadjacent vehicles.

Further, there is provided a novel arrangement and disposition of powerunits and stabilizing means for vertically adjusting the respectivetrack assemblies, whereby such power units and stabilizing means aredisposed within vertical planes common to the respective side frames ofthe trailer superstructure, thereby allowing a maximum width for passageof vehicles between the side-frames.

Also, there is provided a novel arrangement for guiding the power unitsand their associated stabilizers in the longitudinal swinging movementwhich occurs incident to relative vertical adjustment of the oppositeends of a track assembly, to laterally confine such swinging movement topredetermined longitudinal paths, thereby further contributing to thelateral stability of the structure.

In a modified form of the invention, there is incorporated a novelarrangement of the track assembly including longitudinally swingableextensible and contractable power units supporting its opposite ends forindependent vertical adjustment, in combination with a linkage fordetermining the longitudinal position of said track assembly throughoutits range of adjustment.

Exemplifications of the invention are illustrated in the accompanyingdrawings, in which:

FIG. 1 is a side elevation of a vehicle carrier incorporating thepreferred features of the invention.

FIG. 2 is a side elevation, on an enlarged scale, of the tractor shownin FIG. 1.

FIG. 3 is an enlarged detail section on the line 3-3 of FIG. 2.

FIG. 4 is a side elevationon an enlarged scale, of the trailer per se,shown in FIG. 1.

FIG. 5 is a vertical cross-section on the line 5-5 of FIG. 4.

FIG. 6 is a fragmentary side elevation, on a greatly enlarged scale ofthat portion of the trailer containing the forward upper track assemblyand its associated operating and adjusting means.

FIG. 7 is a fragmentary side elevation on a similarly enlarged scale, ofthat portion of the trailer containing the rear upper track assembly andits associated operating and adjusting means.

FIG. 8 is a detail fragmentary view, partly in elevation and partly insection, on the line 8-8 of FIG. 6.

FIG. 9 is an enlarged fragmentary view on the line 9-9 of FIG. 7.

FIG. 10 is an enlarged fragmentary view on the line 10-10 of FIG. 6.

FIG. 11 is an enlarged detail view on the line 11-11 of FIG. 7.

FIG. 12 is a side elevation of a somewhat modified trailer constructionin accordance with the invention.

Referring now in detail to the accompanying drawings, the vehicletransport or carrier of the invention, as exemplified in its entirety inFIG. 1, comprises a conventional tractor 10, and a trailer 12interconnected by a fifth wheel assembly 14. Tractor has a main frame 16on which is supported the superstructure 18 for supporting a vehicleover the cab of the tractor. The trailer 12 has a main frame 20 of thelow bed or drop center type, the rear or trailing end of which issupported on wheels 22 and the forward end of which is supported on thetractor by way of the fifth wheel assembly 14. Supported on the trailerframe 20 is a superstructure comprising relatively spaced identicalvertical sides 26 each consisting of rigid structural members rigidlyinterconnected in a common vertical plane to form a truss-like structureof substantial vertical depth or dimension. The relatively spaced sidesor side frames 26-26 are interconnected at the bottom through the mainframe 20 of the trailer.

The superstructure 18 of the tractor is provided with a rigid trackassembly 28, the forward end of which is pivotally connected by thecross-bar 30 to the superstructure 18 so that the track assembly 28 isswingable about a horizontal axis provided by the cross-bar 30. The rearend of the track assembly 28 thus may be raised or lowered to anydesired position of adjustment by virtue of such swinging movement and apower means is provided for efiecting the said adjustment. To this endit will be seen that a fluid pressure actuated cylinder and piston unithas the cylinder 32 thereof pivotally connected at 34, to the lower endof a vertical structural element 36 of the superstructure 18, while itspiston rod 38 is connected to a slide in the form of a sleeve 40 whichis guided for vertical movement on the structural member 36. Suchmovement of the slide 40 is transmitted through link means 42 to thetrack assembly 28. The fluid actuated piston and cylinder unit 32, 38 iscontrolled in any suitable manner to swingably adjust the track assembly28, whereby to raise or lower the rear end thereof as necessary forclearance of a vehicle carried by the trailer and projecting beneath therear end of the track assembly 28. The slide preferably is provided withone or more holes' 41, adapted to register with holes 43 in thestructural member 36 whereby a locking pin may be employed in customarymanner to fixedly secure the sleeve and track assembly 28 in a desiredposition of adjustment. The main frame 20 of the trailer provides rigidsupport for a substantially continuous trackway extending completely tothe rear end of the trailer, and including a leading section 48 and atrailing or rear section 54 (See FIG. 4). It will thus be apparent thatvehicles driven up conventional ramps and into the rear end of the saidcontinuous trackway may be driven to a location near the forward endthereof.

As shown in FIGS. 1 and 4, a forward trackway or track assembly 44 issupported at its rear end portion by a cross-bar 45 and has its forwardend pivotally and slidably associated with the trailer frame forswinging movement about a horizontal axis extending transversely of thetrailer frame. Referring to FIGS. 4, 6 and 10, for raising or loweringthe rear end of the track assembly 44 to the desired height ofadjustment, the rear end portion of the track assembly 44 on each sidethereof is connected by a link 60 to a slide 62 which, in turn, isguided for movement along a fixed vertical frame 64 of the side panel orwall structure of the trailer. The rear end of the assembly is guidedfor vertical movement by depending guide legs 46 slidable throughsleeves 47 affixed to the trailer side frame members 49. For raising andlowering the slide 62, a v

vertically extensible and contractible power unit 66 is interconnectedbetween the slide 62 and the vertical structural member 64 as by beingpivotally connected to the brackets 68 and 69, respectively, on thebracket and the structural unit.

Thus, in the operation of the apparatus, when it is desired to load avehicle onto the forward lower track assembly 44, the rear end of thelatter is swung downwardly to its lowermost position and the motorvehicle may be driven along the lower tracks or track assemblies abovedescribed onto the track assembly 44, following which the track assembly44, through actuation of the extensible and contractible power means 66,may be raised to a position such that the next vehicle or a substantialportion thereof may project forwardly beneath the track assembly 44.

Located between the opposed side frames 26 is a forward upper trackassembly 70 (shown best in FIGS. 6 and 8), the opposite ends of whichare independently vertically adjustable by the mechanism hereinafterdescribed. Adjacent its forward end the track assembly 70 is pivotallysupported for movement about a horizontal axis extending transversely tothe side frames 26 and defined by rigid tie-bar 72 which is supportedbetween and attached to slides 74, herein shown in the form of sleeveswhich are guided for vertical slid ing movement up and down the verticalside frame members 26, respectively.

For simultaneously raising and lowering the slide 74 and the tie-bar 72supported thereby, there is provided a conventional extensible andretractable power'unit 78. The power unit 78 for each slide has itsupper end connected to the slide by means of a bracket 80 while thelower end thereof is connected to the supporting frame 26 by way of abracket 82.

It will be understood that the power units 78 for the respective slides74 are controlled and and actuated in coordinated manner to maintain thetie-bar 72 in a horizontal position at all times. In addition to itsfunctions of supporting the front end portion of the upper trackassembly 70 and defining a pivotal axis about which such assembly isswingable, it will be seen that the tie-bar 72, in conjunction with theslide 74, serves to tie together the upper portions of the respectiveside frame members 26 so that they may mutually reinforce each otheragainst side s way. The tie-bar 72 is fixedly connected to therespective slides 74 and the forward end portions of the separate tracksof the track as sembly 70 are rigidly connected in spaced relation to arigid tubular structure or member 83 through which they are rotatablyjoumalled on the tie-bar 72 and, in addition, are rigidly interconnectedin fixed spaced relation to each other.

Adjacent their rear ends the relatively spaced tracks of the upper trackassembly are fixedly interconnected by rigid bar 84. Carried by this baradjacent its opposite ends, and in common planes with the respectiveside frames 26, are brackets 86, each of which is pivotally connected at88 to one of the two telescopically associated members 90 of anextensible and retractable stabilizer designated 92 in its entirety. Theother member 94 of such stabilizer 92 is connected at 96 to a bracket 90affixed to the vertical side frame member For raising and lowering therear end portion of the upper track assembly 70, each of the extensibleand retractable power units 102 has its opposite ends connected by wayof brackets 104 and 106, respectively, to the members 90 and 92 of anextensible telescoping stabilizer and is disposed for extension andretraction parallel to the stabilizer 92 so that the stabilizer andpower unit will extend and retract together and, in fact, cooperate insuch manner as to form a common extensible and retractable mechanism inwhich the stabilizer 92 functions primarily to maintain alignment and toimpart rigidity to the entire structure, both during extension andretraction thereof and during transport of a vehicle on the upper trackassembly. Holes 91 and 93 are provided in the stabilizer sections forreception of a conventional locking pin. As in the case of the powerunits for the forward end portion of the track assembly 70, the powerunits 102 for the rear end portion thereof are actuated and controlledin any conventional manner and by any conventional means to achievesimultaneous and equal extension thereof so as to maintain the rear endsof the separate tracks of the track assembly 70 at a common level or, inother words, horizontally opposed to each other, being assisted in thisby the rigid interconnection between these tracks provided by thetie-bar 84.

It will be apparent that within the rather substantial range of movementof the power units 78 and 102, the opposite end portions of the trackassembly 70 are independently vertically adjustable, both to facilitatethe passage of vehicles therebeneath during loading operations andthereafter, when supporting a vehicle, to lower the respective ends ofsame independently to the greatest extent possible, while achievingclearance of vehicles disposed therebeneath.

At the rear end of the trailer, and as illustrated in FIGS. 7, 9 and 11,between the side frames 26 the rear upper track assembly 108, the tracksof which are rigidly interconnected by transverse members 110 and 112,respectively, in substantially the same manner as in the forward trackassembly 70. The tubular front cross-frame member 110 of the assembly isjoumaled on a transverse tie-bar 114, the opposite ends of which arerespectively connected to and supported by slides 116 in the form ofsleeves which are guided for movement up and down the vertical sideframe members 118. An extensible and retractable power unit 120 isconnected at one end to a bracket 122 carried by each slide 116 and thelower end of the same unit is fixedly connected through a bracket 124 tothe side frame structure, whereby extension and contraction of the units120 will raise and lower the slides 116.

As in the case of the upper track assembly 70, the power units 120 oneach of the side frames are actuated in coordinated relation tosimultaneously raise and lower their respective slides 116.

Also as in the forward upper track assembly 70, the rear end of the rearupper track assembly 108 is raised and lowered about the pivotal axis114 and maintained in any desired position of adjustment about such axisby means of an extensible and contractable power unit 126 which isstabilized and maintained in alignment by stabilizer 128, comprising anassembly of telescoping tubes, one of which is pivotally connected at130 to a bracket 132 carried by said assembly. The lower end of thestabilizer is pivotally connected at 134 to a bracket 136 affixed to themain frame 20 of the trailer.

The opposite ends of the stabilizer 128 are connected to the oppositeends of the power unit 126 by way of the brackets 138 and 140 so thatthe two will be extended and retracted together, the power unit servingto supply the necessary extension and retracting force while thestabilizer supplies the desired rigidity to maintain the parts inalignment while supporting the very substantial weight of a vehicle onthe rear upper track assembly 108.

It is to be particularly noted that a high degree of lateral stabilityis secured by virtue of the specific relationship of the stabilizer 128and power unit 126; with respect to their associated side frames 26. Thestabilizer 128 on each side of the trailer is guided for swingingmovement about its pivot 134 between and in sliding engagement with therelatively spaced plates 142442 at the rear end of each side frame. Byvirtue of this arrangement, lateral stability of the track assembly 108and any vehicle supported thereon is assured.

It will be apparent that either the front or the rear end of the reartrack assembly 108 may be vertically adjusted independently of theother, the opposite ends of the track assembly being swingable about thepivotal axes 114 and 130, respectively, responsive to raising orlowering of either end relative to the other and may be arranged at anyof various desired heights.

In addition to the two adjustable upper track assemblies abovedescribed, the vehicle carrier of the invention also includes anadjustable middle track assembly, designated 144 in its entirety andbest shown in FIG. 4, this also being arranged for independent verticaladjustment of its opposite ends by suitable power units.

As with the track assembly heretofore described, the laterally opposedtracks of the assembly 144 are rigidly interconnected in spaced parallelrelation in any suitable manner. Slides such as 146 guided for verticalmovement on the transversely opposed side frame members support betweenthem a cross-member 148 on which the forward end of the the middle trackassembly 144 is supported for vertical swinging movement. Each slide 146is raised and lowered to selected positions of adjustment by means of anextensible and retractable power unit 150, pivotally connected to themain frame 20 at 152 and pivotally connected to the slide 146 at 154.

The rear end of the middle track. assembly 144, when in its lowered ortransport position, as shown in full lines in FIGS. 1 and 4 rests on andis supported at either side by fixed supports 258 in the respective sideframe members 100.

In each of the side frame members 100 an extensible and retractablepower unit 164 extends diagonally from its pivotal connection 166 to themain frame and has its upper end pivotally connected at 168 to the rearend portion of the track assembly 144. Thus extension of the diagonallydisposed power unit 164 will raise the rear end of the track assembly144 and retraction thereof will lower the rear end of the said assembly.

It will therefore be apparent that the opposite ends of the trackassembly may be independently raised and lowered as desired throughsuitable actuation of their respective power units 150 and 164, and willbe stabilized in all lateral directions by virtue of the guiding actionof the vertical side frame members 100 and 118 with respect to theslides or sleeves 146 and the telescoping guides 156.

It is to be particularly noted that the track assembly 144, by suitableaction of its power units 150 and 164 may be raised from its full linelowered or transport position of FIG. 4 to a fully elevated position,shown in broken lines in FIG. 4, in which it spans the gap between thefront and rear upper track assemblies, to serve as a bridge between themfor loading and unloading purposes.

Attention is particularly directed to the fact that in the abovedescribed structure, the only interconnections between the opposed sideframe 26, except for the main frame extending between the bottom edgesthereof, is provided by the vertically adjustable tie-bar and pivotmembers 72 and 114 of the front and rear upper track assemblies 70 and108, respectively, and by the vertically adjustable tie-bar and pivot148 of the middle track assembly 144. By virtue of this arrangement,there are no fixed cross-ties or interconnections between the sideframes at locations above the lower track assemblies which cannot bevertically adjusted to permit ready movement there-past of vehiclesincident to loading and unloading of the carrier. At the same time theafore-said combined tie-bars and pivots function in all of theirpositions of vertical adjustment to provide rigid interconnectionsbetween the opposed side frames at suitably located points to contributeappreciably to the lateral stability of the entire super structureconstituted by said side-frames and to the vehicles supported thereby.

It will be appreciated further that all of the power units and theirassociated stabilizing means heretofore described are located invertical planes common to their respective side frames, so as to avoidunduly increasing the width of the carrier and so as to permit maximumusage of the space between the side frames for positioning of vehicles.

In the use of the vehicle carrier of this invention, in order to loadthe vehicles onto the track assembly 28 of the tractor, the rear uppertrack assembly 108 has its rear most end fully lowered by appropriateactuation of its power unit 126. Referring to FIG. 1, a vehicle A isthen driven up a usual temporary ramp structure extending from the rearend of said track assembly 108 to the ground onto the fixed trackssupported between the opposite sides of the main trailer frame 20,thence across the middle track assembly 144 (which, for this purpose,will have been raised to its fully elevated spanning position betweenthe track assemblies 70 and 108, as illustrated in broken lines in FIG.4), and thence by way of usual temporary ramps or tracks from the trackassembly 70 onto track assembly 28 overlying the cab of the tractor 10.In the same manner, the next two vehicles are positioned on the trackassemblies 70 and 108, respectively, the vehicle being designated,respectively, as A, B and C in a direction from front to the rear.

In order to load the remaining vehicles, the rear or trailing end of therear upper track assembly 108 is substantially fully raised by suitableactuation of its power unit 126 to provide clearance for passagetherebeneath for a further vehicle D. The middle track assembly 144 ismaintained fully raised at both ends thereof by its associated powersources or units 150 and 164, respectively, to permit the vehicle D tomove therebeneath and thence on to the forward lower track assembly 44,the rear end of which will have been swung downwardly through actuationof its associated power unit 66. After the vehicle D is received on theforward lower track assembly 44, the rear end of the latter is elevatedto provide clearance therebeneath for the next vehicle E which is movedonto the lower ramps and advanced forwardly to the position shown, themiddle track assembly 144 still being in its position. At this time, theforwardly presented end of the vehicle E will project beneath the tackassembly 44, while the rearwardly presented end thereof will projectbeneath the track assembly 144. The forward end of track assembly 144will then be lowered until it just clears the said vehicle and the rearend thereof will be lowered substantially to the greatest extentpermitted by its associated power unit to rest on the stationarysupports 158 as shown in full lines in FIG. 4.

The track section 54, which is hinged at 169 to the frame 20 is swungupwardly to the broken line position of FIG. 4, and supported in thatposition in any suitable manner while the vehicle F is driven into therear end of the trailer and over track section 54 onto the middle trackassembly 144. The last vehicle G then is driven into the rear end of thetrailer on the lower track ways into substantial abutment with thepreceding vehicle F, the trailing end of the middle track assembly 144being then raised by its associated power unit 120 sufficiently toprovide clearance for reception therebeneath of the forwardly presentedportion of the said vehicle G.

In accordance with usual practice, all of the vehicles upon beingreceived in their proper positions, are firmly tied down or securedagainst movement in conventional manner and when all are positioned onthe carrier, the various track assemblies are all vertically adjusted bythe respective power units to position each vehicle in the lowestposition practicable, without damaging vehicles therebeneath, so thatthe center of gravity of the loaded carrier is at minimum height and nopart of any vehicle loaded thereon will project upwardly higher than apredetermined vertical clearance which must be maintained in order thatthe loaded carrier may pass safely beneath bridges and overpasses.

It should be readily apparent that the various extensible andretractable power units such as 78, 102, 120 and 126, employed forraising and lowering the track assemblies, may be of various typeswithin the scope of the invention. For instance, it is contemplated thatsuch units may consist of double acting hydraulic piston and cylinderunits of a conventional nature or that they might comprise, forinstance, interengaged threaded elements disposed for relative rotationto effect the extension and/or contraction of the unit and such relativerotation may be produced by power driven means, such as electric motors.Further, it will be appreciated that the various stabilizers, such as 92and 128, may be omitted, providing the power units are made sufficientlyrigid to withstand the operational stresses to which they will besubjected and to provide firm stable support for the various trackassemblies and the vehicles supported thereon for transport.

In general, the manner of loading the vehicles onto the trailer issimilar to that disclosed in the US. Pat. No. 3,163,459 to Dyo'ri et al.of Dec. 29, 1964.

In the modified embodiment of the invention shown in FIG. 12, except asto the features hereinafter specifically noted, the arrangement issubstantially similar to that described in connection with the preferredembodiment, and corresponding parts are designated by similar but primedreference characters. Thus, as in the preferred embodiment, there aredisposed between the opposite sides of the main side frames 26', and atsub stantially the level thereof, a substantially continuous series ofnormally stationary track assemblies or tracks defining a roadway forthe loading and unloading of vehicles extending along substantiallywithin the entire length of the lower frame from the rear end thereof tothe adjustable lower track assembly 44' at the forward end of the frame.This lower track assembly 44' is vertically swingable about its forwardor leading end under the control of a power unit 66' to which it isconnected by a link 60', just as in the preferred embodiment.

Similarly, as in the preferred embodiment, the forward end supported forswinging movement about a horizontal tie-bar 72' interconnected betweenthe slides 74' so as to define a vertically adjustable axis for swingingmovement of the track assembly 70'. The opposite end portions of thetrack assembly 70' are independently vertically adjustable as in thepreferred em bodiment by means of the power units 72' and 102'.

The present modified embodiment, however, differs from the earlierdescribed preferred embodiment primarily in the omission of the middletrack assembly, such as 144, or the preferred embodiment and in thesomewhat difi'erent arrangement of the stabilizing means for the rearupper track assembly 108. It will be recalled that in the preferredembodiment above described, the forward end of the rear track assembly108 was swingably supported by the tie-bar 114, guided by the sleeves116 for vertical movement up and down fixed vertical frame members 118,under the control of power units 120 interconnected between the trailerframe and the guide sleeves on either side of the trailer. Thus, onlythe power unit and its associated stabilizers 126 and 128, respectively,at the rear or trailing end of the track assembly 108, were swingable ina longitudinal direction to accommodate longitudinal displacement of therear end of the track assembly arising from the relatively independentvertical adjustment of its opposite ends. In the present arrangement,the power units 120' and 126' and their associated stabilizers 118' and128, respectively, are swingable longitudinally, and the longitudinalposition of the track assembly 108' is determined and maintained bylinks 170 preferably interconnecting the opposite sides of the trackassembly 108 to the respective opposed side frames 26' of the trailer.Each such stabilizing link 170 is thus pivotally connected to itsadjacent side of the assembly 108' at 1 14' and is pivotally connectedto its associated side frame 26 at 174.

The power unit 120 has its opposite ends respectively connected to thetelescopically associated members of a stabilizer 118', the oppositeends of which are pivotally connected at 175 and 176, respectively tothe track assembly 108 and the main trailer frame 20. Thus, it will beseen that as the forward end of the track assembly 108 is raised andlowered by actuation of the power unit its forward end will be guided ina path of movement concentric to the pivotal connection 1 14 between thelink and the side-frame 26.

The opposite sides of the track assembly 108' are rigidly tied togetherin spaced parallel relation by conventional means, including a tie-bardefining the pivot 114', and the upper ends of the power units 120' andtheir associated stabilizers or guide 118 on the opposite sides of thetrailer are interconnected in rigidly spaced relation by the upper trackassembly or frame 108'. Each such power unit 120' and its associatedstabilizer 118' is disposed for swinging movement in the vertical planeof its side frame 26 in the space between the relatively aligned andadjacent end portions or frame members 178 and 180, respectively, andbetween guide plates 182 which interconnect the said frame members orsections 178 and 180. Guide plates 182 thus confine and guide the powerunits 120' and their associated stabilizers in predetermined andparallel longitudinal paths to thus prevent side sway of these parts andtheir associated track assembly 108. At the same time the track assemblyties together the upper ends of these said parts and acts through theassociated power units and stabilizers to crossconnect and laterallystabilize the opposed side frames 26'.

The rear end of the track assembly 108' is adjustably supported insubstantially the same manner as in the preferred embodiment by thepower unit 126 and its associated stabilizer 128' both swingable about apivotal connection 134' to the frame 20' of the trailer. It will be seenthat these parts are guided in their swinging movement by frame sectionsin the form of guide plates 142' disposed on opposite sides of eachpower unit 126' and its associated stabilizer 128'. These plates 142'thus impart lateral stability to the structure in the same manner asheretofore described in the preferred embodiment.

The manner of loading and unloading the modified trailer will be readilyapparent, being substantially similar to that above described inconnection with the preferred embodiment, except that the middle trackassembly 144 and the operation thereof described in connecu'on with thepreferred embodiment are omitted.

It is to be particularly noted that in each of the illustratedembodiments of the invention, each track assembly is firmly securedagainst horizontal displacement, both from side to side and in a foreand aft direction, as for instance by the cooperating slides 74, 146,116 in the preferred embodiment, together with the guide plates 142, andby corresponding slides and the link 17 0 and guide plates 182 in theembodiment of FIG. 12.

It is to be understood that the drawings and descriptive matter are inall cases to be interpreted as merely illustrative of the principles ofthe invention rather than as limiting the same in any way, since it iscontemplated that various changes might be made in the various elementsto achieve like results without departing from the spirit of theinvention or the scope of the appended claims.

Having thus described my invention, I claim:

1. A vehicle transport comprising a low-bed trailer having relativelyspaced apart vertical side-frames, a plurality of relativelylongitudinally spaced cross-ties extending horizontally between andinterconnecting the upper portions of said side-frames in fixedly spacedrelation, means interconnecting said cross-ties to the respectiveside-frames for vertical adjustment, first power means for verticallyadjusting each of said crossties, said cross-ties constituting the solemeans interconnecting the upper portions of said side-frames, uppertrack assemblies carried by the respective crossties for verticalswinging movement about horizontal axes defined by the respectivecross-ties, and further power means connected to each said trackassembly at locations eccentric to said axes for swinging adjustmentabout said axes, said transport including transversely opposed pairs ofslides guided for vertical movement on the respective side frames, eachsaid cross-tie interconnecting and being supported between one of saidpairs of slides for vertical adjustment therewith, said first powermeans being operatively associated with the respective said slides.

2. A vehicle transport as defined in claim 1, in which said side-framesrespectively include pairs of transversely opposed vertical framemembers, said slides, respectively, being guided for vertical movementon said vertical frame members.

3. A vehicle carrier as defined in claim 2, in which each said slidecomprises a tubular sleeve slidably encompassing and guided for verticalmovement on one of said transversely opposed vertical frame members.

4. A vehicle transport comprising a low-bed trailer having relativelyspaced apart vertical side-frames, a plurality of relativelylongitudinally spaced cross-ties extending horizontally between andinterconnecting the upper portions of said side-frames in fixedly spacedrelation, means interconnecting said cross-ties to the respectiveside-frames for vertical adjustment, first power means for verticallyadjusting each of said crossties, said cross-ties constituting the solemeans interconnecting the upper portions of said side-frames, uppertrack assemblies carried by the respective crossties for verticalswinging movement about horizontal axes defined by the respectivecross-ties, and further power means connected to each said trackassembly at locations eccentric to said axes for swinging adjustmentabout said axes, said transport including transversely opposed pairs ofslides guided for vertical movement on the respective side frames, eachsaid cross-tie interconnecting and being supported between one of saidpairs of slides for vertical adjustment therewith, said first powermeans being operatively associated with the respective said slides, saidupper track assemblies being relatively longitudinally spaced apart,there being a middle track assembly below said upper said trackassemblies in the space therebetwe'en', means for independentlyvertically adjusting the opposite longitudinal end portions of saidmiddle track assembly, and a further pair of slides guided for verticalmovement on the respective side frames, said middle track assembly beingconnected to said slides for swinging movement about a horizontal axisand, with said slides, interconnecting said side frames in relativelyfixed transversely spaced relation.

5. A vehicle transport as defined in claim 4, including means pivotallyconnected to said middle track assembly at a location eccentric to eaxis of its said swinging movement for vertically adjusting the latterabout said axis.

6. A vehicle transport including a trailer having a low bed, relativelytransversely spaced vertical side frames supported thereon, a trackassembly supported between the upper portions of said side frames forindependent vertical adjustment of its front and rear end portions,power means for effecting such independent adjustment comprisingtransversely spaced pairs of rigid extensible and retractable parallelpower units, the upper ends of one such pair being pivotally connectedto the forward end portion of said assembly and the upper ends of theother said pair of units being pivotally connected to the rear endportions of said assembly, the lower ends of said power units beingpivotally connected to said respective side frames, and meansinterconnecting said one assembly to said respective side-frames tocontrol the longitudinal position of said assembly with respect to saidside frames, said last-mentioned means comprising a stabilizing linkpivotally connected to each said side frame for vertical swingingmovement and having a free end pivotally connected to said assembly.

1. A vehicle transport comprising a low-bed trailer having relativelyspaced apart vertical side-frames, a plurality of relativelylongitudinally spaced cross-ties extending horizontally between andinterconnecting the upper portions of said side-frames in fixedly spacedrelation, means interconnecting said cross-ties to the respectiveside-frames for vertical adjustment, first power means for verticallyadjusting each of said cross-ties, said cross-ties constituting the solemeans interconnecting the upper portions of said side-frames, uppertrack assemblies carried by the respective cross-ties for verticalswinging movement about horizontal axes defined by the respectivecross-ties, and further power means connected to each said trackassembly at locations eccentric to said axes for swinging adjustmentabout said axes, said transport including transversely opposed pairs ofslides guided for vertical mOvement on the respective side frames, eachsaid cross-tie interconnecting and being supported between one of saidpairs of slides for vertical adjustment therewith, said first powermeans being operatively associated with the respective said slides.
 2. Avehicle transport as defined in claim 1, in which said side-framesrespectively include pairs of transversely opposed vertical framemembers, said slides, respectively, being guided for vertical movementon said vertical frame members.
 3. A vehicle carrier as defined in claim2, in which each said slide comprises a tubular sleeve slidablyencompassing and guided for vertical movement on one of saidtransversely opposed vertical frame members.
 4. A vehicle transportcomprising a low-bed trailer having relatively spaced apart verticalside-frames, a plurality of relatively longitudinally spaced cross-tiesextending horizontally between and interconnecting the upper portions ofsaid side-frames in fixedly spaced relation, means interconnecting saidcross-ties to the respective side-frames for vertical adjustment, firstpower means for vertically adjusting each of said cross-ties, saidcross-ties constituting the sole means interconnecting the upperportions of said side-frames, upper track assemblies carried by therespective cross-ties for vertical swinging movement about horizontalaxes defined by the respective cross-ties, and further power meansconnected to each said track assembly at locations eccentric to saidaxes for swinging adjustment about said axes, said transport includingtransversely opposed pairs of slides guided for vertical movement on therespective side frames, each said cross-tie interconnecting and beingsupported between one of said pairs of slides for vertical adjustmenttherewith, said first power means being operatively associated with therespective said slides, said upper track assemblies being relativelylongitudinally spaced apart, there being a middle track assembly belowsaid upper said track assemblies in the space therebetween; means forindependently vertically adjusting the opposite longitudinal endportions of said middle track assembly, and a further pair of slidesguided for vertical movement on the respective side frames, said middletrack assembly being connected to said slides for swinging movementabout a horizontal axis and, with said slides, interconnecting said sideframes in relatively fixed transversely spaced relation.
 5. A vehicletransport as defined in claim 4, including means pivotally connected tosaid middle track assembly at a location eccentric to the axis of itssaid swinging movement for vertically adjusting the latter about saidaxis.
 6. A vehicle transport including a trailer having a low bed,relatively transversely spaced vertical side frames supported thereon, atrack assembly supported between the upper portions of said side framesfor independent vertical adjustment of its front and rear end portions,power means for effecting such independent adjustment comprisingtransversely spaced pairs of rigid extensible and retractable parallelpower units, the upper ends of one such pair being pivotally connectedto the forward end portion of said assembly and the upper ends of theother said pair of units being pivotally connected to the rear endportions of said assembly, the lower ends of said power units beingpivotally connected to said respective side frames, and meansinterconnecting said one assembly to said respective side-frames tocontrol the longitudinal position of said assembly with respect to saidside frames, said last-mentioned means comprising a stabilizing linkpivotally connected to each said side frame for vertical swingingmovement and having a free end pivotally connected to said assembly.